Also…
(a) Is the road to be one-way/one lane (e.g. a loop road, similar to what you find in a lot of campgrounds), two-way/two-lane (probably the most typical design), or something else? The owner may have specific criteria for how traffic moves around the site. If not, the design team (including, but not limited to, the civil) should sit down and figure this out and present it to the owner for approval or modification.
(b) Is the roadway width limited to just the travel lanes (e.g. a two-lane road might be 24' wide to accommodate two 12-foot lanes) or is a shoulder desired and, if so, how wide?
(c) Are turnouts needed at various locations? Some of the prisons I have designed have had one-lane exterior patrol roads with turnouts at each guard tower. The purpose of these turnouts is to allow one or two vehicles to be parked on pavement but out of the traveled way.
(d) What types and sizes of trucks will be using this road? Truck turning radii affects horizontal curve alignments and intersection designs. In any event, the smallest design vehicle will most likely be the largest fire truck operated by the local fire department and they should be able to provide that information. Along these lines, you may also have fire hydrants that are remote from the main circulation roadways. If so, it may be necessary to provide paved fire truck access to these fire hydrants. Fire truck access does not have to be paved per NFPA (I have used gravel), but many fire departments require it.
(e) What is the maximum speed for the road? For a private project, this might come from the owner or the civil might recommend a design value.
In addition, the project will almost certainly require one or more paved parking lots. The local agency should have minimum parking standards that will apply, but if not the owner should have some idea of how many passenger and other vehicles to accommodate. I did the civil design for an ethanol plant about ten years ago and the owner's parking requirements far exceeded the local agency's requirements. We also made the parking spaces slightly over-sized at the owner's request to better accommodate dualie four-door pickups.
Because each project and each site is different, there are many other questions a savvy civil is going to want answers to regarding the on-site roads and parking areas. Where such answers are not available (or haven't yet been decided), the savvy civil will be able to come up with reasonable suggestions.
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"Is it the only lesson of history that mankind is unteachable?"
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